Sync Plugin server

---

Implementation for HunterPie's SyncPlugin. Currently deployed on: https://amadare-mhw-sync.herokuapp.com/

Websockets API

For websockets there is simple flow that needs to be done. Note that type member isn't case-sensitive. Currently, it is available on https://amadare-mhw-sync.herokuapp.com/ root.

Here is list of all possible messages in vague order:

1. Check version with HTTP GET /version. It will return valid numberic version.
2. Connect to websockets endpoint /connect. Client is expected to make ping requests (e.g. send Ping frame with 0x9 opcode https://tools.ietf.org/html/rfc6455#section-5.5.2), otherwise connection will be closed after 5 minutes of inactivity. Data frame containing literal word "ping" will work as well.
3. Every member should then send SetSession message to bind this connection to specific session:

{
  "type": "SetSession",
  "sessionId": "<your session id>",
  "isLeader" true | false
}

4. On every session members update, SessionState message will be sent to all members:

{
    "type": "SessionState",
    "playersCount": <players count>,
    "leaderConnected": true | false
}

5. Leader can then send Push messages that will be propagated to all other non-leader members:

{
  "type": "Push",
  "sessionId": "<your session id>",
  "data": <monster data>
}

NOTE: specific model for monster data aren't defined for server.

6. Non-leader members will receive same exact message described in 5.
7. Any member can receive ServerMessage message that is expected to be displayed on client. This can be used to notify about some errors or maintenance warnings.

{
    "type": "ServerMessage",
    "text": "<Server message text>",
    "level": "trace" | "debug" | "info" | "warn" | "error"
}    

7. To unbind connection from session, Close message can be sent by any member:

{
  "type": "Close"
}

Message compression

It is expected for clients to use deflate-message compression algorithm, but without context takeover since at the time of writing, client doesn't support it.

Logging

Under /logs.html endpoint tool to monitor logs is available. It will display server logs at realtime. It will also display logs that are sent to /logs/add endpoint. Expected format:

{
    timestamp: number, // unix timestamp in milliseconds
    level: string, // log level: debug, trace, info, warn, error
    msg: string, // message text
    text: string, // redundant full entry representation (with time and level)
    user: string, // user name
    room: string
}

Array of objects of this type is also supported.

These logs will be sent to /logs/listen?roomId=<roomId> endpoint. They are not stored anywhere. So for further analysis it will be useful to dump them into DB. cheapass-logs-dumper will do exactly that: connects to specified server and listen for all received logs to DB.

Hosting with Docker

If you want to host this yourself, simply use the docker-compose supplied in the project root. Please note that you may need to configure your webserver to pass the websocket. Here is a simple example for Nginx:

server_tokens off;

server {
    listen 80;
    server_name hunterpie-sync.domain.com;

    access_log /var/log/nginx/hunterpie-sync.domain.com.log;
    error_log  /var/log/nginx/hunterpie-sync.domain.com.log error;

    sendfile off;
    add_header X-Robots-Tag none;

    location / {
                    proxy_pass http://127.0.0.1:5001;
    }
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
}

upstream hunterpie-sync {
    # enable sticky session based on IP
    ip_hash;

    server localhost:5001;
  }